1. FIELD OF THE INVENTION
The present invention relates to flush tank control apparatus for a toilet and particularly to valves that may be buoyant and non-buoyant depending upon how the valve is attached to the valve operating system.
2. PRIOR ART
Flap valves and similar flow control devices for use with flush tank control apparatus are well known in the prior art. Specifically, there are several devices that are in use that are buoyant for allowing the full flush cycle to take place when the valve operating system handle is operated. In addition, there are non-buoyant valves used for partial flushes, more accurate control of water uses, and ease of quick shutoff of water if backup occurs in the flush system. Other devices used to limit the water used in a flush operation include dualmode devices which have a partial flush and a full flush mode; water column devices which have dams or other partition devices which can prevent a full flush when needed; and devices which allow for premature closing the flush valve. These devices all suffer from significant disadvantages such as complexity and the fact that they can only be used in specific applications. The present invention provides that the valve can be used in a system where a buoyant valve is desired or it can simply be turned over and used as a non-buoyant valve if so desired. Furthermore, many devices in the prior art are not adaptable for use with different heights and valve seat angles with respect to the overflow pipe which is used with pivot connections on the valve for operation. Many valves provide for two rearwardly extending arms that are connected to the overflow pipe. It is very important that the valve design make provision for adequate sealing with different seating angles and to do so with the valve used in a buoyant or non-buoyant configuration. Thus, the present invention overcomes the attachment disadvantages of devices in the prior art, illustrated by U.S. Pat. No. 3,702,012. Finally, the design of the valve in accord with the present invention is self-centering and accordingly positive seating is assured in either the buoyant or non-buoyant state of the valve unlike any other known prior art valve.